Results of our research show, that in female fetuses the amount of lipids at the beginning of the 6th month of prenatal ontogenesis reaches 83 μmol/l. By the middle of the 7th month, lipid content in skeletal muscle has increased by 7,5 times, compared to the previous month (602 μmol/l), which can be considered a critical period of development. At the 8th month of prenatal development, lipid content is the lowest – 48 μmol/l. Later, by the end of the third trimester, lipid index becomes stabilized and is 217 μmol/l. In male fetuses this indexes are somewhat different - 155 μmol/l at the beginning of the 6th month. Further, its content is almost tripled and by the middle of the 7th month it reaches 442 μmol/l, which is a critical period for male fetuses. The last trimester is characterized by a decrease: at the 8th month - up to 362 μmol/l, on the 9th month – up to 130 μmol/l.